Cigarette smoking continues to be a major public health problem. Almost 54 million Americans continue to smoke despite repeated warnings about the adverse effects of smoking on health. In spite of the vast amount of research on smoking, it is still not clear why so many continue to smoke given overwhelming evidence of smoking's harmful effects. One hypothesis is that many individuals fail to quit because they need or think they need cigarettes in order to reduce self-perceived tension or stress levels so that they may function more effectively on the job, in social situations, or even when alone. Very little empirical research has been done however on relationships between psychosoical stress and smoking. The purpose of this study is to examine relationships between these variables. Specific aims are: (1) to determine how pervasive and critical psychosocial stress is as a factor in maintaining smoking; (2) to examine demographic and psychosocial characteristics of those who smoke to reduce stress compared to other types of smokers, ex-smokers, and never smokers; (3) to ascertain whether smoking actually improves performance on complex problem-solving tasks; (4) to determine optimal quitting strategies for high-stress smokers. This project will involve 150 smokers, 150 ex-smokers, and 150 never smokers who are currently participants in the Normative Aging Study of the Veterans Administration in Boston. Structured interviews, personality and perceived stress assessments will be performed. Existing smoking data from the Normative Aging Study will be utilized for some research questions, and an experimental component involving a subset of 180 subjects will assess effects of smoking and stress on complex cognitive problem-solving tasks. Knowledge of relationships between smoking and stress can be useful in the design of smoking cessation programs for high-stress smokers, as well as for increasing our understanding of the role of stress as a factor in maintaining the smoking habit.